RESUMO
AIM: To study the role of interleukin-2 (IL-2) and mediobasal hypothalamus (MBH) in analgesia produced by Coriolus versicolor polysaccharide peptide (PSP). METHODS: The IL-2 antiserum was injected i.c.v. or i.p. and the MBH was destroyed electrolytically. RESULTS: PSP i.g. 1 g.kg-1.d-1 for 6 d increased the pain threshold in tail stimulation-vocalization test in rats. This PSP-produced analgesia was blocked by i.c.v., but not i.p., IL-2 antiserum and disappeared after electrolytic lesion of MBH. CONCLUSION: The analgesia produced by PSP is mediated by IL-2 which is activated by PSP and interacts with IL-2 receptors in the MBH.
Assuntos
Analgésicos não Narcóticos/farmacologia , Hipotálamo Médio/fisiologia , Polyporaceae , Polissacarídeos/farmacologia , Animais , Feminino , Soros Imunes/farmacologia , Injeções Intraventriculares , Interleucina-2/imunologia , Interleucina-2/fisiologia , Masculino , Limiar da Dor , Peptídeos/isolamento & purificação , Peptídeos/farmacologia , Polyporaceae/química , Polissacarídeos/isolamento & purificação , Ratos , Ratos WistarRESUMO
AIM: The nervous mechanism of the immune potentiating effect of Coriolus versicolor polysaccharides peptides (PSP) was studied in Wistar rats. METHODS: The unit discharge of the mediobasal hypothalamus (MBH) neurons was recorded extracellularly and the lymphocyte proliferation was measured. RESULTS: PSP 1 g.kg-1 ig for 5 d increased the T-lymphocytes and promoted T-lymphocyte proliferation in spleen and peripheral blood. This promoting effect of PSP was blocked by MBH lesion. PSP increased the discharge frequency of MBH neurons, but no increase in discharge frequency was observed after treatment of PSP plus immune inhibitor, cyclosporin A. CONCLUSION: MBH is involved in the immune-potentiating effect of PSP.
Assuntos
Adjuvantes Imunológicos/farmacologia , Hipotálamo/fisiologia , Neuroimunomodulação/efeitos dos fármacos , Polyporaceae/química , Proteoglicanas/farmacologia , Animais , Divisão Celular/efeitos dos fármacos , Eletrofisiologia , Feminino , Masculino , Neurônios/fisiologia , Distribuição Aleatória , Ratos , Ratos Wistar , Linfócitos T/citologiaRESUMO
The effects of hypothalamic arcuate nucleus (ARC) or anterior lobe of pituitary (AL) stimulation on the nociceptive responses of thalamic parafascicular (Pf) neurons were studied in rats with electrophysiological technique. The results showed that ARC stimulation could inhibit the nociceptive discharges of Pf neurons, namely, the immediate inhibition because of its very short latency and duration. AL stimulation could also inhibit the nociceptive discharges of Pf neurons, but this inhibition was a delayed one because of its longer latency and duration. Hypophysectomy diminished the immediate inhibition due to ARC stimulation, while ARC lesion diminished the delayed inhibition due to AL stimulation. Both kinds of inhibition were blocked by dexamethasone pretreatment. The above results suggest that neuroendocrine relationship between ARC and AL is involved in pain modulation.